Magnetic recording media have been encouraging an extensive demand in accordance with advance and diversification of magnetic recording apparatuses, and have been widely applied to video tapes, audio tapes and so forth.
A running durability is requested to magnetic recording media because of repeated use, and in recent years, the magnetic recording media capable of recording in a high density is strongly demanded.
Usually, a magnetic recording medium is comprised of a non-magnetic support having thereon a magnetic layer, and conventionally a running durability thereof has been improved by strengthening the support.
However, numberless fine protuberances usually existing on the surfaces of most non-magnetic supports make it difficult to form thereon a magnetic layer with a uniform thickness, and to provide a magnetic recording medium capable of recording in a high density.
Further, the protuberances are liable to be exposed on a surface of a magnetic layer, and the exposed protuberances are sometimes cut to small pieces in the course of a calender treatment, which are transferred to the magnetic layer.
The exposed protuberances and the transferred small protuberances are liable to result in poor performances of a recording medium.
On the other hand, a magnetic recording medium using a non-magnetic support without any protuberances sometimes has such problems in running durability as edge folding.